Error check on invalid icon paths

[Tjark-Kuehl]

Hi,
I just ran in an issue where I couldnt figure out why the package wasnt loading my icon correctly.
After looking deeper into it I found out that I had prefixed my icons with .svg
I know that its not documented like this but I still wasted an hour or so.

Could we implement either an error check or a string replacement here?
https://github.com/danielstgt/svg-vue/blob/master/src/svg-vue.vue#L20

get() {
    const cleanPath = this.icon.replace(new RegExp('.svg$'), '');
    return cleanPath.replace(new RegExp('.'.replace(/([.*+?^=!:${}()|\[\]\/\\])/g, '\\$1'), 'g'), '/') + '.svg';
}

or just throw an error

get() {
    if(this.icon.endsWith('.svg')) {
        throw new Error('invalid icon path');
    }
    return this.icon.replace(new RegExp('.'.replace(/([.*+?^=!:${}()|\[\]\/\\])/g, '\\$1'), 'g'), '/') + '.svg';
}

other then that I really appreciate the package :)