tests: add lexer tests

Signed-off-by: Marc-Antoine Perennou <Marc-Antoine@Perennou.com>
core: rename reserved_keyword funcs

Signed-off-by: Marc-Antoine Perennou <Marc-Antoine@Perennou.com>
core: define separators API

Signed-off-by: Marc-Antoine Perennou <Marc-Antoine@Perennou.com>
tests: add test-separator

Signed-off-by: Marc-Antoine Perennou <Marc-Antoine@Perennou.com>
implement ku-separator

Signed-off-by: Marc-Antoine Perennou <Marc-Antoine@Perennou.com>
core: define KuToken API

Signed-off-by: Marc-Antoine Perennou <Marc-Antoine@Perennou.com>
core: define KuToken struct

Signed-off-by: Marc-Antoine Perennou <Marc-Antoine@Perennou.com>
core: implement KuToken

Signed-off-by: Marc-Antoine Perennou <Marc-Antoine@Perennou.com>
core: rename NONE

Signed-off-by: Marc-Antoine Perennou <Marc-Antoine@Perennou.com>
core: define lexer api

Signed-off-by: Marc-Antoine Perennou <Marc-Antoine@Perennou.com>
fix lexer tests

Signed-off-by: Marc-Antoine Perennou <Marc-Antoine@Perennou.com>
core: define lexer struct

Signed-off-by: Marc-Antoine Perennou <Marc-Antoine@Perennou.com>
core: implement lexer

Signed-off-by: Marc-Antoine Perennou <Marc-Antoine@Perennou.com>
Merge branch 'wip/lexer'

* wip/lexer:
  core: implement lexer
  core: define lexer struct
  fix lexer tests
  core: define lexer api
  core: rename NONE
  core: implement KuToken
  core: define KuToken struct
  core: define KuToken API
  implement ku-separator
  tests: add test-separator
  core: define separators API
  core: rename reserved_keyword funcs
  tests: add lexer tests