Small doc fixes (#4110)

* fix adoc links and some typos

* actually fix links

substrate/docs/Structure.adoc

@@ -11,7 +11,7 @@ Substrate is split into multiple levels with increasing opinion and decreasing f
 
 * primitives
 * client
-* PAINT (formerly `paint`)
+* PAINT (formerly `srml`)
 
 Putting all these components together we have:
 
@@ -24,26 +24,26 @@ Putting all these components together we have:
 
 * _found in_: `/primitives`
 * _crates prefix_: `sp-`
-* _constrains_:
+* _constraints_:
 ** must be `[no_std]`
 ** crates may not (dev-)depend on crates in other subfolders of this repo
 
-In the lowest level, substrate defines primitives, interfaces and traits to implement any on-chain substrate transition system and its interactions with the outside world. This is the lowest level of abstraction and opinion everything else builds upon.
+In the lowest level, Substrate defines primitives, interfaces and traits to implement any on-chain Substrate transition system and its interactions with the outside world. This is the lowest level of abstraction and opinion that everything else builds upon.
 
 === Client
 
 * _found in_: `/client`
 * _crates prefix_: `substrate-`
-* _constrains_:
+* _constraints_:
 ** crates may not (dev-)depend on any `paint-`-crates
 
 In the client you can find a set of crates to construct the outer substrate-node, implementing outer runtime interfaces, thus it depends on `runtime`. It provides the outer building blocks like transaction queue, networking layer, database backend, full* and light-client support.
 
-=== PAINT (formerly `paint`)
+=== PAINT (formerly `srml`)
 
 * _found in_: `/paint`
 * _crates prefix_: `paint-`
-* _constrains_:
+* _constraints_:
 ** all crates that go on chain, must be `[no_std]`
 ** must not (dev-)depend on anything in `/client`
 
@@ -53,11 +53,11 @@ PAINT, the Parity Application Interface for Network-wide Transitions, is a set o
 
 * _found in_: `/test`
 * _crates prefix_: `substrate-test`
-* _constrains_:
+* _constraints_:
 ** only helpers may be published
 ** purely testing crates must be `publish = false`
 
-All tests that have to pull (dev)-dependencies out of their substree and would thus break the dependency rules, are considered intergration tests and should be stored in here. Only helper-crates in here shall be published, everything else is expected to be non-publish.
+All tests that have to pull (dev)-dependencies out of their subtree and would thus break the dependency rules are considered intergration tests and should be stored in here. Only helper-crates in here shall be published, everything else is expected to be non-publish.
 
 === Binaries and template
 
@@ -69,8 +69,7 @@ We also provide some binaries pulling from the components creating full applicat
 
 * _found in_: `/bin/node`
 
-The default (testing) application pulling together our recommended setup of substrate-client with a wasm-contracts-supporting paint-runtime.  The node pulls it all together, constructs the (upgradable) runtime and wires up the client around it. You can find an example client, which includes a full wasm-contracts chain in  `node`. This is also what is being build and run if you do `cargo run`.
-
+The default (testing) application pulling together our recommended setup of substrate-client with a wasm-contracts-supporting paint-runtime.  The node pulls it all together, constructs the (upgradable) runtime, and wires up the client around it. You can find an example client, which includes a full wasm-contracts chain in  `node`. This is also what is being built and run if you do `cargo run`.
 
 ==== Node Template
 
@@ -107,4 +106,3 @@ Subkey is a client library to generate keys and sign transactions to send to a s
                            +-------------------+
 
 ....
-