Modified the way idapythonrc executes. Added more support to some modules. Implemented modules for segments and enumerations.

main:
    Added a custom module importer for the base/ set of modules.
        This makes all of the base/ set of modules available globally without needing to mess with paths
        This also enables one to hide modules that aren't intended to be exposed.
    Added a lazy module importer for each subdirectory of idascripts
        (disabled by default due to it being pretty alpha)
    Shuffled a few comments around so that they'll appear in the module's help()
    Modified __root__.py to import a few more handy modules
    Added support to clean up the namespace that idapython thrashes so hard
    Removed a few stray module imports here and there
    Made base/declaration and baes/comment private using the new custom module importer

base/segment:
    implemented .create, .load, and .map for creating segments within the database
    removed code that deals with selectors as that might not exist in all architectures
    added .repr and a few other attribute-like methods to segment
    modified base/database to accomodate for changes made in this module

base/enum:
    added a few attributes for enum objects
    implemented support for interacting with members of an enum object.

base/structure:
    modified member_t in base/structure to only use FF_YWRD if it is defined within idaapi

base/database:
    replaced usage of idc with idaapi
    grouped the definitions of similar functions together
    fixed a potential bug on ida64 related to checking for 0xffffffff instead of idaapi.BADADDR
    fixed iterate_refs to adjust itself if address is not pointing to an instruction/data head.
        also decided to hide since it's only intended to be used internally.

base/function:
    added .by* for getting a func_t object
    modified a few functions to use a func_t object instead of an ea
    moved functionality from .{get,set}Comment and .{get,set}Name into .comment and .name properties
    regrouped similar functions together